By S&S Co. Advocates & Solicitors · Published 20 September 2026 · Informational content, not legal advice — see our disclaimer
Provisional vs. Complete Specification
An inventor can file either a provisional specification — a preliminary description that secures an early priority date while the invention is still being developed or tested — or a complete specification containing the full, final description and claims. Where a provisional application is filed first, the complete specification must be filed within 12 months, failing which the provisional application is treated as abandoned and the priority date is lost.
Filing and Examination
The application is filed with the Indian Patent Office (in the appropriate jurisdictional branch based on the applicant's or, for foreign applicants, their patent agent's address) along with the prescribed forms and fees. Examination is not automatic — a Request for Examination must be filed separately, currently within 48 months of the priority or filing date, to bring the application into the examination queue. Once examined, the Controller issues a First Examination Report raising any objections, which the applicant must respond to within the prescribed period, commonly followed by a hearing if objections remain unresolved.
Publication and Opposition
A patent application is ordinarily published 18 months after filing (or earlier, on request), opening a window during which a pre-grant opposition can be filed by any person under Section 25(1) of the Patents Act, 1970. After grant, a separate post-grant opposition window is available under Section 25(2) for a limited period, during which only a 'person interested' can oppose.
Timeline and Costs
End-to-end timelines vary considerably depending on the technology area, whether expedited examination is sought, and whether any opposition is filed, but applicants should generally expect a multi-year process from filing to grant in the ordinary course. Government fees vary by applicant category — individuals, startups and small entities generally pay reduced fees compared to large entities — and by the number of claims and pages in the specification; current fee schedules should always be checked against the Patents Rules' latest fee schedule at the time of filing, since these are revised periodically.
Maintaining the Patent
Once granted, a patent must be maintained through the payment of annual renewal fees to keep it in force, for a maximum term of 20 years from the filing date of the application. Missing a renewal fee deadline (subject to a grace period with a surcharge) can result in the patent lapsing before its full term, so patentees should track renewal dates carefully, particularly for a patent portfolio spanning multiple jurisdictions and renewal cycles.
Frequently Asked Questions
What is the difference between a provisional and complete patent specification?
A provisional specification is a preliminary description filed to secure an early priority date while the invention is still being finalised; the complete specification, containing the full description and claims, must then be filed within 12 months, or the provisional application is treated as abandoned.
Is examination automatic once a patent application is filed?
No. A separate Request for Examination must be filed, currently within 48 months of the priority or filing date, to bring the application into the examination queue — filing the application alone does not trigger examination.
How long does a patent last, and does it need renewal?
A granted patent lasts a maximum of 20 years from the filing date, but must be maintained through annual renewal fee payments to stay in force — missing a renewal deadline, beyond any grace period, can cause the patent to lapse before its full term.
References & Further Reading
This article references the following statutory provisions. Readers should always verify current rules, fees and timelines against the applicable statute and rules as amended, since these are revised from time to time.
- Patents Act, 1970, Sections 9, 11B, 25(1), 25(2) and 53, as amended.
- Patents Rules, 2003, as amended, including the current fee schedule.